After 6 months of prototypes and testing I am proud to introduce the K-ONE coffee filter (Metal Chemex filter).

The Idea: The love of single cup coffee. Attempt to reduce or solve the issues of paper. Paper can add flavor and produces garbage.

The Brewer: Chemex glass brewer. We really enjoy using the Chemex because it brews and also acts as the holding chamber and server for the brewed coffee. The thought was to make the filter fit the Chemex because of its design, use and that many people already owned one.

Producing the filter: With the help of friends and an engineer the first 5 prototypes were made. All had different hole patterns with the idea of contributing to the brewing. 1 design was chosen and 2 more prototypes were ordered for further testing.

The Result: A Stainless steel, laser welded filter that produces what we like to call a hybrid brew. It resembles a French Press in it has oils and some sediment but has the look, feel and control of a pour over.

The Name: K-ONE just a silly name that is a play off of the word cone and one cup at a time with a K for my name. Cheesy but it needed a name for manufacturing.

We released the filter for the first time yesterday at our “Preview Day” at Coava. Starting Monday July 5th we will be open everyday. Please come by and say hello. We would love to show you around and brew you a cup with the filter.

Looks like you've effectively made your Chemex brew more like a Hario V60 brew, with permeation on all surfaces of the cone. In your prototyping, did you ever try limiting the permeation (perforations) to just the part where the paper filter of the Chemex naturally opens up (the tip-area of the cone that is normally exposed)? That would have maintained the Chemex brewing dynamic, but replaced a metal screen filter for the paper. Looks like what you've got now is a "floating-filter" type brew dynamic, like the Hario V60 or the wire dripper in this Japanese YouTube video, which is significantly different from the Chemex brew dynamic.

Nick. I did try that. I decided to not go with that design as it didn't change the brew at all since the water never really gets too high on the filter. When the holes are reduced too much then clogging becomes an issue along with brew times an extraction.

The design was modeled after the Hario but with the Chemex as the holding device.

To answer questions of if they are for sale. Not at this time. I only have enough for our use and don't have the funds or time to produce enough to make the cost worth selling. Plus the design is somewhat still in prototype mode. The model pictured is the medium filter. I have 2 addition models that have different hole patterns for even further testing. One has more holes the other has less holes.

One of my ideas is to use all 3 filters as a "set". The user can then decide which filter to use as to add another method of controlling the brew process. Then the grind pour and filter can each be changed to alter the extraction. Currently in pour over the paper or swiss gold filter cannot be altered only the grind and pour. If the cones go into production ever or sold, I would like to sell as a 3 piece set.

Yeah, I'd be interesting in trying this filter, as well. Not for use full-time in my Chemex, but maybe for certain coffees. I have found that one of the things that has endeared me to the Chemex for years, was the clean cup it gives, mostly because of the thicker filter. I'd be interested to see what the end result would be with this one...

Just curious - how do the results stack up relative to the gold filter for Melitta style pour-over? I like both Chemex and Melitta (or Hario) style paper pour-over very much when properly prepared, but have not had success brewing a good cup with the Melitta style gold mesh filter (not claiming that it's a fault of the system - could be wrong grind or technique on my part, or even just personal taste).

When I saw this originally posted to Coffeed.com, I was dismayed. The trend has been for people to try to brew pourover coffee fairly quickly (under 2 minutes start-to-finish). To this day, I have not had one cup of coffee brewed on a pourover-style dripper in less than 3 minutes that, to me, tasted like a full, well-developed brew. The KONE, as far as I could see, would follow this continuum. It would take a Chemex, which can indeed make a great cup of coffee if used with skill, and ruin it. The mesh filter would most probably speed up the extraction greatly, which in my opinion, mitigates one of the best attributes of the Chemex.

Then I visited Coava.

Matt Higgins made me a cup of their El Salvador Santa Sofia. It was, and is to this day, the best pourover coffee I've had in a coffeebar.

The trick seems to be to maintain a fairly low and slow pour, resisting the temptation to fill-up the filter much above the coffee bed. This is only my theory, but to my observation, keeping it low actually allows the perforations to clog slightly, helping to further slow down the flow rate and brew. Matt's target brew time was 3 minutes 30 seconds... which is my target total brew time as well. If you fill it up too much, your water will bypass the coffee too much. So as with any brewing device, there's are right ways and wrong ways to use it. With some devices, even the right way doesn't really perform that great (cough! V60 cough!). The KONE, though, can make some really badass coffee!

Just a completely unsolicited, unbiased endorsement for the KONE. Good stuff Keith and Matt!

SeanCapistrant wrote:Has anyone tried the K-One with a V60. i'm curious to see how it does with the ribbed sides. Or if it would even work at all.By the way, they look way cool.

I tried it the other day using the same technique I use with the Chemex. There is no noticeable difference, it still behaves the same way and extracts the same way. Because the K-ONE doesn't actually touch the sides of the Chemex brewer (unlike the paper) there is still extraction out the sides of the K-ONE, and not just out the bottom.

What would/could be interesting is having the K-ONE with only the bottom inch or so perforated and the rest un-perforated and I'm guessing it'd work closer to the paper, and also be less finicky with pouring technique as there'd be no 'side extraction', and no 'channelling' or under-extraction' should you pour against the sides of the filter.